1. Field of the Invention
The present invention relates to computer system security. More particularly, the present invention relates to a system and method of detecting and blocking malicious code on a computer system.
2. Description of the Related Art
Attackers attempt to steal passwords, for example, to gain access to the bank accounts of a bank customer. To prevent this sort of theft, instead of assigning a bank customer a single static password that can be reused by an attacker if stolen, the password is continuously changed or is only valid for a single login. In this manner, even if the password is stolen, the password will not be valid when the attacker attempts to use it.
However, even if a password is only valid for a single logon, an attacker can still gain access to the bank accounts of the bank customer using an active attack, sometimes called a piggybacking attack. More particularly, the attacker installs piggybacking malicious code on a bank customer's (the victim's) computer system. The attacker waits until the bank customer logs into the bank, and piggybacks malicious transactions in the context of the bank customer's otherwise legitimate banking session. Accordingly, to facilitate secure transactions, any piggybacking attack should be detected and defeated.